Mold and core structure



c. wEssx-:L 2,429,146

MOLD AND CORE STRUCTURE Oct. 14,1947.

Filed Dec. 11, 1942 6 sheetssheet 1 Oct. 14, 1947. c. wEssEL 2,429,146

MOLD AND CORE STRUCTURE Oct. 14, 1947. C, WESSEL MOLD AND CORE STRUCTURE Filed Dec. l1, 1942 6 Sheets-Sheet 5 Oct. 14, 1947.

C. WESSEL MOLD AND CORE STRUCTURE 6 Sheets-Sheet 4 Filed Dec. l1, 1942 C. WESSEL MOLD AND CORE STRUCTURE Oct. 14, 1947.

Filed Dec. 11. 1942 6 Sheets-Sheet 5 1 l I l Oct. 14, 1947. Q WESSEL MOLD AND UORE STRUC'lUl-UV Filed Dec. 12.1, 1942 6 Sheets-Sheet 6 Zf///////////// JMVII w m fg f, x III M.

www w Patented Get. 14, l1947 2,429,146 MOLD ANDCORE STRUCTURE Carl Wessel, Chicago, Ill., assignor to Carl Wessel and Lew W. Cleminson, Chicago, Ill

Application December 11, 1942, Serial No. 468,621

The present inventionrelates to castings, ma-

- chines,`and methods oi casting, and is particularly concerned with improvements in the subject-matter disclosed in my prior application, Ser.

No. 251,092, filed January 16, 1939, which has issued as United States Letters Patent No. 27,287,- 848, June 30, 1942, Method of casting.

One of the objects of the invention is the provision of an improved casting machine and improved method of casting, which is adapted to produce better castings and better metal stock of various shapes, more efficiently and more economically than can be done by the methods and apparatus of the prior art.

Another object of the invention is the provision of an improved tilting machine adapted to carry out the methods covered by my prior patent and certain improved methods of casting.

Another object of the invention is the provision of an improved method and apparatus for 'tot :a2-151) accomplished by this method and apparatus are substantially the same as those enumerated in prior patent, the methods of which this appacasting, by means of which the dimculties of removing the mold from the casting, and the casting from the machine, are greatly reduced so as to expedite the making of castings.

Another object of the invention is the provision of an improved mold by means of which the mold parts may be more quickly separated or assembled and by means of which the casting may be more easily removed from the mold and machine.

Another object of the invention is the provision cian improved machine of the tilting type,

in which provision is made for tilting the ladle on its axis so as to secure special results in the flow of metal into particular parts of the mold, and also for the purpose of leveling up the machine.

Another object of the invention is the provision of an improved mold and improved cores by means of which cored apertures of any desired shape may be made in the casting and the core is very conveniently removed when the casting is nished.

Another object of the invention is the provision of an improved method of making cores for castings, and the provision of a method of making molds.

Another object of the invention is the provision of an improved casting or metal stock having a higher degree of uniformity of crystal structure, a better nished surface, so as to eliminate the necessity for machining, the elimination of the undesirable results of shrinkage, ilaws, pipes, and the perfect lling of the mold.

Other objects and advantages of the invention ratus is adapted to carry out with even better results.

Further objects and advantages of the invention will be apparent from the following description andthe accompanying drawings, in which similar characters of reference indicate similar parts throughout the several views, and of which there are ve sheets.

Fig. 1 is a side elevational View of a casting machine embodying the invention;

Fig. 2 is a front elevational view of the casting machine;

Fig. 3 is a to'p plan view of the casting machine;

Fig. 4 is a sectional view, taken on a plane passing through the axis of the casting, showing the open half of the mold and the cores in place for the formation of a casting, after the application of the other mold half;

Fig. 5 is a view in perspective of a special core of the type used in Fig. 4;

Fig. 6 is a vertical sectional view, takenon a plane passing through the axis of the ladle, showing the mold in elevation and illustrating the application of' a burner flame to the surface of the metal and to the mold. The dotted line position illustrates one of the extreme positions to which the ladle may be tilted, although it is not necessary to tilt the ladle in every case to this eX- tent.

Fig. 7 is a fragmentary sectional View, taken through the mold, showing the position of the mold parts before the beginning of the mold I'llling operation;

Fig. 8 shows the position ofthe mold parts and the molten metal as the mold filling operation begins;

Fig. 9 is a similar View, showing the mold after it has been filled and is being subjected to the pressure of a head of metal in the ladle, while the metal casting is congealing;

. Fig. l0 is a similar view, showing the mold and casting after the ladle'and mold have been tilted back tothe position of Fig. 7, but before the mold has been removed;

Fig. 11 is a sectional view, taken through the casting made with the mold illustrated, the section being taken` on a plane passing through the aXes of the twoI boresfof the casting, with the destructible core still' in place;

Fig. 12 is a similar view` of .the casting after the destructible core has been removed;

The apparatus preferably includes a supporting framework (Fig. 1), indicated in its entirety at 20, for pivotally supporting a ladle 2| by means of trunnions 22 carried by the bearing members 23.

Other modes of tiltably supporting the ladle 2| may be employed, but I prefer to utilize trunnions 22, which are located so that the ladle is normally held in upright position when it is charged with a suitable charge of molten metal.

The framework 2|) may consist of a plurality of angular metal members, four of such members forming a rectangular base 24, the base members being secured together by welding at the corners.

At each of the corners of the bese 24, the framework 20 is provided with upwardly extending columns 25, 26, 21,"and 28. At, their upper ends the vertically extending frame members 25 and 26 are joined by a, horizontal frame member 29, also made of angle stock, a'nd the upper ends of the vertical frame members 21, 28 are joined by a horizontal frame member 30.

The bearing members 23 may each consist of cast metal members in the form of a channel, having side flanges 3|, 32, and a -base flange 33, which is provided with apertures for receiving the screw bolts 34, which secure these bearing members to the horizontal frame members 29 or 30.

The web 35 of each bearing member is provided with a vertically extending slot 36, the lower end of the slot being provided with a half circular border 36' so that it is adapted to serve as a bearing for the trunnion 22. The trunnion members 22 are identical in shape and construction, but are oppositely disposed on the ladle 2l.

Each trunnion may comprise a substantially cylindrical shaft 31, which is xedly secured to a supporting strap 38, which may be of substantially rectangular shape and provided with inwardly extending slots 39 and 40 at its upper and lower ends.

The trunnion 31 may be provided with a head 4i, which is formed by, means of a groove 42 located between the end of the trunnion and the supporting strap 38. The groove 42 may be of rectangular cross section so that the trunnion has a portion of reduced cylindrical size at 43 for engaging in the bearing slot 36 against the bearing surface 31.

The annular thrust surfaces 44 and 45, which form the walls of the slot 42, serve to engage the two faces of the web 35 of the bearing member 23 and prevent endwise motion of the trunnions in the bearings.

The two upwardly extending portions of the frame 20, which are formed by the vertical parts 21, 28 and horizontal member 30, and the vertical parts 25, 26 and horizontal member 29, are spaced from each other, leaving the framework open at the front and back so that the ladle and .its associated parts may be tilted freely between these upwardly extending bearing supporting portions.

The ladle 2| may consist of a metal shell, and the metal shell may take various different forms, but is preferably made with a cylindrical body portion 46 and a flat bottom portion 41. The cylindrical portion 46 of the shell may terminate with the upper edge 48 of its wall in substantially the same plane for engagement with a cover member 49, except that the cylindrical Wall 46 is'. provided ,with a partially circular cut-out portion at 5B, the groove 5|! also registering with a cut-out portion 5| located in the cover 49, forming a burner opening 52.

The burner opening is of sufficient size (Fig. 6)` to permit the burner discharge pipe 53 to be directed into the inner chamber 54 of the ladle at the various different angles and to be so oriented that its flame may impinge upon the free surface 55 of the molten metal 56 and be reflected upward toward the opening 51 in the mold 58.

In addition to this, the opening 52 is of sufficient size 'so that it may serve as an aperture for filling or emptying or cleaning the ladle, and it also serves to discharge the gases of combustion which issue from the ladle as a result of the action of the burner 59.

At diametrically opposite sides the shell 2| is provided with the` longitudinally extending frame member comprising a metal strap 60, such as steel, which is welded, or otherwise permanently secured l,to the metal shell 2|'and provided with tlzie outwardly extending threaded screw bolts 6|, 6

These screw bolts are spaced from each other such a distance relative to the location ofthe slots 39, 40 that a considerable vertical adjustment is permitted with respect to the location of the trunnion member 22 upwardly or downwardly on the side of the ladle 2|.

The trunnion members are clamped in place by means of nuts on the bolts 6|, 62; and by means of this adjustment the ladle and its mold may be tilted in a lateral direction so as to level up the machine, Where a laterally symmetrical casting is to be made in the mold.

In the event casting is being made in a mold which is not symmetrical laterally, and it is desirable to facilitate the flow of the metal toward one side of the mold before it reaches the other, these adjustable trunnions may be used to tilt the entire ladle from the vertical axis, and to facilitate the flow of the metal to the desired points in the mold.

Except at the opening 52, the upper edge of the shell 2| is provided with an angle iron 63, the vertical flange of which is curved cylindrically to t the outside of the shell wail 46. The horizontal flange of the angle 63 provides an extended bearing surface for the cover 49. All of the metal parts of the ladle 2|, frame 20, and mold 58 are preferably made of a metal of high melting point, such as steel, or steel alloy, although in some cases the mold parts may be made of cast metal.

The cover 49 may consist of a circular plate of sheet metal (Fig. 2) adapted to cover the upper end of the shell 2| and to have its bordercoincide with the outer edge of the horizontal flange of the angle 53, except that the cover is provided with the out out portion at 5|, bordered by two substantailly radially extending lines and providing an opening 52.

The cover may be secured to the shell 46 by a plurality of through screw bolts 64, passing through apertures in the cover,y and threaded into apertures in the angle 63. In some embodiments of the invention the cover may be riveted in place or welded.

The framefpreferably supports a latching lever 250, which is pivotally mounted at 25| and urged into latching position by a spring 252. It has a notch 253 for engaging a keeper 254, which is carried by the ladle and may be actuated by a foot pedal connected to a connecting link 255.

The ladleY 2| is preferably heat-insulated by having its shell 46 lined with a relatively thick wall 65 of heat-insulating and heat-resisting refractory.

The refractory 65 covers the inside of the cylindrical wall 46 and the bottom 41, and forms a substantially cylindrical chamber 54, which has its lower corners rounded at 66 for effective cleaning and complete discharge of the ladle in use or during the cleaning operations.

The wall of refractory B5 may be b/uilt up in the lower part 0f the shell 45 by using a suitable inner core, after which the core is`withdrawn, and additional upper sectional Ycores'are used to form the upper wall surfaces.

The refractory not only extends up to the cover 9 at the outer walls of the shell 46, but it is provided with an upwardly extending tubular neck 81, surrounding a ladle discharge conduit 68 and passing through a circular opening 69 in the cover plate 49.

The neck 61 may be formed integrally with the side wall 0f refractory 65, and an additional upper wall portion may be formed integrally with the side Walls and neck of refractory. The upper Wall portion 10, being supported from the side walls of refractory 65, at the open mouth 52 the refractory is gradually curved outward, as indicated at 1| and 12.

Another layer 13 of refractory of the same or of a different kind may extend over the upper wall surface 14 and over the horizontal flange of the angle 63 to insulate the cover plate 49 from the shell 2| and angle iron 63.

The tubular neck 61 (Fig. 6) may be surrounded by an insulating collar 10 of refractory, which supports a metal plate 15, having a tapered aperture 16 registering with the discharge con--` duit 68.

The plate is secured to the cover` plate i9 by a plurality of screw bolts having their heads located above the plate 15, the bolts passing through plate 15 and through the insulating axle 1li, and being threaded into the cover plate 49.

Thus the p'ate 15 is heat-insulated from thecover plate o fitheladle, except for the heat that is transmitted through the securing bolts 16.

planesurface 18 so`a`s-tof1ocate the axis of the. '4 mold atan, angle to thehorizontal free surface 455 ofthe molten metal. 1

The refractory member 'l1 also has a conduit 00 passing through -.it, and registering with the discharge conduit 68 and-aperture 16 of the ladle 6 the bolts 82, which transmit some heat to the plate 15.

The two halves of the mold 58 are indicated by numerals 8| and 83, and these membersare substantially similar in shape and construction, each having half of a cavity formed therein to provide the casting cavity. The mold halves are each preferably built' up of a plurality of metal layers of laminations, the laminations engaging each other with lapped and ground plane surfaces, and the separate sections or laminations of the half mold member 8l are indicated by th numerals Sli- 88.

The joints between thesesections are indicated by the numerals 89-92, and the lower plane surface of the section 88, which engages the re- Vcommunicating by means of a Y-shaped conduit 90.

The body of the casting is indicated by the numeral 99, and it is provided on its rearside with four laterally projecting attaching flanges |00, lill, |02, and |03.

The borders of the mold portions, which form the ends of these attaching anges, are indicated at |04, |05, |06. Thus it is desirable to have the rst section 88 terminate along the line |06, which is the upper edge of attaching flanges |00,' 0|. The'next section 85 may be of the same width as the attaching anges |00, |0l. The next section 86 of the mold forms that portion of the casting which is between the attaching flanges, and it may terminate at its lower plane surface 9|, which is on the same plane as the upper edge of the attaching nanges |02,.^|08.

The next section 81 of the moldmay be of the same vertical width as the attaching anges l|012, |03, and the lowermost section 88 isof suicient depth vertically to form the lowerbarrel portion of the casting 95 and to make `these g barrel portions of suiiicient length so that when rel portions of'su'ii'icient length are left.

The two bores 96 and 91 in the casting .95

' are formed -by suitable .permanent cores |01,

and vplate 15; The conduit 80- communicates with f the inlet to the mold, .andthe refractory mem 4ber 11 serves as additional heat insulationv for vinsulating the mold from the ladle.

The fixed half 8| of the mold 58 may be iixedly secured to the plate 15 and refractory member 11 by a plurality of screw bolts 82, having their heads located below the plate 15, the bolts Apassing upward through the. plate 15 and through' the refractory 11 and being threaded into the mold half 8 I Thus this portion of the mold is heat-insulated from the ladle by the refractory 11, except for |08. These permanent cores arealmost cylindri- -cal in shape ,lbut have very slight taper, such as four -thous'an'dths of an inchfon a seven inch core. v

-This makes the cores frusto-.conical so that theymay be removed from the casting bybeingf In order` vto hold the permanent cores |01,

l 08 in place, they are supportedbythe cylindrical plugs |10, Hl, which fit in the circular boresy l |2, ||3 in the mold. These circular boresv are,

of course, formed by :half cylindrical grooves in each'half of the mold. Each plug -Hl), is

` provided'on its upper plane side with a metal washer H4, H5, the washer having a greater The plugs ||2, ||3 and washers H0, are provided with tapered bores ||1, Ils for receiving the tapered permanent cores |01, |08 so that the plugs and washers have a forced fit, and are frictlonally held in predetermined position on the permanent cores.

Each plug is preferably provided with a plurality of longitudinally extending external grooves ||9 extending the full length of the groove and communicating with radially extending grooves |20 located either at the lower side of the washer ||4, or in the top wall of the plugs H0, i

Il' located in'thfe'top wallof the plug! I0.'

the grooves also'xtnd 'radially into the" uppe` surface ||6.of the mold 'so-as to provide' cornmunicatior'r between the external atmosphere and the interionchambers |2|, |22gof. the; mold through grooves`ll9, |20.A A

These grooves are Afrom two tl'rQusandths-to ness, and in some cases grooves smaller than two thousandt'hs of an inch in depth may be provided in greater number topermit the slowV passage of the air out of the mold and elect a perfect lllng of the mold.

The grooves are too small relative to the condition of the molten metal to pass the molten metal, and for this pur'pose the size of the grooves depends on the liquidity of the molten metal.

When the mold is lled at a temperature of molten metal close to the melting point, the liquidity of the metal is low, and the groves have a lesser tendency to -form a disguration'on the end surface orT the casting.

Similar grooves are also provided at |23 on the inside 'o'f each plug |I0, l|| for venting the air from the mold at the corners adjacent the permanent cores |01, |08.

The grooves |23 also communicate with radial grooves to permit the communication of the grooves with the atmosphere.

The casting in question is formed with a pair of barrels comprising enlarged cylindrical portions |24, |25, |26, |21 at each end, joined by a flat and thick central rectangular portion |28 and by intermediate substantially cylindrical portions |29 and |30 (Fig. 16).

In order to provide this shape, the mold has the cylindrical bores ||2, ||3, and cylindrical bores of a slightly larger 'size |3I, |32 at each end of the mold. The intermediate bores |33, |34 in the mold are smaller to form the smaller portions |29, |30. Each` half mold has a flat wall portion |35 between the'permanent cores and cavities, `and the ilat wall-portions are spaced from each other on the 'separate halves of the molds, to

'provide a thick central body portion |28, which joins the two barrels.

At its lower end the mold is provided with a pair of bores |36, |31 (see Fig 4) of the same size as the bores 2, H3, and the two bores |36, |31 may merge into a single oval opening |38 at the lower end of the mold, and communicating with the conduit 51 inthe refractory member 11.

The present casting is adapted to be formed with the laterally projecting ears l00-l03, and the mold sections 85 are formed with the recess surrounded by the walls |04, |05, |06 to form these ears. The rest of the surface of each section 85 is indicated by the numeral |39, and the sections 85, 81 of the mold are utilized to form ribs |40 on the xed half of the mold."

The ribs |40 (Fig. 6) are bound by the face surface |39 and the two side walls |4|, |42. They 'ofconduits joining the two barrels or bores 96,

91, the conduit being indicated by the numeral 98 in- Fig. 11. Such a Y-shaped conduit may be used for a two-way valve in order to direct fluid .iii one direction or another into the bore 94.

eight thousandths o; an'incn m depth'a'n thick- -2' -When'one port |46 (Fig. 11) is closed by a cylinder, another port |41 may be opened, and both Ports may be controlled by means or a cylinder in the b ore 91, closing port |48.

`This Y-shaped conduit extends across the intermediatebody portion of the casting from one bore ,'96 -to the other bore 31; and for this purpose I prefer to use a destructible core |49 of thetype illustrated in Fig. 5.

This destruetible core has a larger cylindrical stem portion |50,'which forms the port |48, and two smaller cylindrical stem portions |5|, |52 for forming the ports |46, |41 and thev connecting conduits.

The destructible core is made by means of a special method, fully to lie-disclosed hereinafter; and it is preferably of such construction that it may be dissolved by means of a suitable solvent passed through the casting after the casting has been completed.

I prefer to construct the core of such materials and construction that it is destructible merely by the use of water as a solvent, so that the core may be dissolved at the same time that the casting is quenched in water.

In other embodiments of the invention it may be made soluble in certain quenching oils or other solvents.

In order to support the core |49 in the mold I prefer to provide a cylindrical socket |53 for the cylindrical end |50 of the destructible core in the permanent core |08. Similar cylindrical sockets |54, |55 are formed in the permanent core |01 for receiving the end portions |5|, |52 of the destructible core |49.

Each of the permanent cores |01, |08 is provided with an axially extending air escape bore |56, |51 extending at its upper end to a radially extending bore |58, |59 for communicating with the atmosphere.

At its lower end the bore |56 communicates with a radial bore |60 extending into the socket |53. At its lower end the bore |51 in the permanent core 01 communicates with radially extending bores |6 |62, which communicate with sockets |54 and |55.

The axially extending bores |56 and |51 may extend the full length of the permanent cores, if desired, for purposes of convenience, as no harm is done by having the bore at the lower end of the permanent core.

|56 to |62, inclusive, may be of any suitable size for permitting the escape of air and other gases from the destructible core |49, when 'heat is applied to it.

For example, they may be of the proportions shown in the drawing, or they may be made considerably larger for freer passage of the gases from the interior of the mold.

The separate sections 84--88 of the mold are held in axial alignment by means of metal dowel pins, preferably two in number, one being located These bores and conduits in each of the side portions of the mold on each side of the cavity, in Fig. 4.

The dowel pins and the bores extend through all of the mold sections. 'I'he dowel pins have a frictional nt in the bores. For example, the bores. for the dowel pins are indicated by the numerals |65 and |68 (Fig. 4), while the dowel pins are indicated by the numerals |61, |68.

In addition to the dowel pins for aligning the sections of the mold 85-88, these dowel pins may extend downward into the refractory member 11 in the case of the ilxed portion of the mold 8|, but in the movable portion of the mold 83, the dowel pins terminate short of the lower surface of the mold half 83.

The mold sections are also preferably secured together by through bolts, comprising at least one on each side of the mold, and the through bolts pass through aligned bores in the separate mold sections 84-81.

The through bores are indicated by the numerals |69, |10 (Fig. 4), and the through bolts by the numerals 1|, |12. The clamping nuts |13-I14 at the-top engage the threaded portions of the bolts and 'draw the bolt sections tightly together. The separate mold sections are, of course, accurately lapped and ground at their engaging surfaces and provided with inner mold cavity formations, which are accurately aligned, as indicated, by the bolts and dowel pins.

The machine is preferably provided with means for withdrawing the permanent cores, and this may comprise a suitable le'ver |15 and its associated parts. For this purpose the cover plate 49 may be provided with a. pair of columns |80, |8| for pivotally lever |15.

The columns |80, .|8| have laterally turned attaching flanges |82, |83, through which the screw fbolts |84 pass, to be threaded into threaded bores in the cover 49.

At their upper ends these columns are provided with aligned bores |85 for receiving the shaft the bores.- The columns |80 vand |8| may be supporting the rear end of they If the permanent cores are not large enough to provide a sufilcient body, they may be provided with a head 205 at the top, as shown in Fig. 4 on the core |01, or the head may be omitted, as shown, at the upper end of core |08. The upper end of each core'is provided with a through bore 206, 201 for receiving the shaft 202, which also passes through the bore 203 of the link 20|.

The shaft 202 preferably has an easily removable flt in the bores, and is secured in one of the bores by means of a set screw 208, such as that shown, threaded into the upper end of the core |01. Thus the cores may be readily disconnected -from their operating linkage, if desired; Vbut usually the cores are disconnected by withdrawing the pin |91 whenit is necessary to change them or clean them or make some other adjustment.

The lever |15 withdraws the cores by means of the application of an upward force to its rounded end |09, and by reason of the taper ofthe permanent cores, they may be withdrawn. Those portions of the destructible core |49 which are in the sockets |53--i55 are readily sheared o.

The destructible core |49 is made by molding this core in a suitable mold, having a cavity corresponding in shape to the external area, and

braced by a transverse frame member |81 secured i to each column by screw bolts |88 adjacent the top.

The lever |15 may be constructed out of a tubular pipe, the cylindrical portion |89 at the front end serving as a handle. Above the mold the pipe of which the lever |15 is formed may be split into a pair of parallel legs |90, |9|, separated by a slot |92.

The legs |90, |9| may be bent diagonally outward at I 93, and may be provided with pivot flanges |94 at each end, the pivot flanges having apertures providing bearings for the pivotal movement of the lever on the shaft |86. A tubular spacer |95 may =be placed on the shaft |86 between the pivot flanges |98.

The legs |90, |9| may be provided with a pair of aligned aperturesI |96 for receiving the removable pivot pin |91, having a pointed end |98 and a, nger loop |99.

The pivot pin |91 also passes through a bearing bore 200 in the link 20|. The link 20| comprises a short strap of metal pivotally secured to the lever |15 at the pin |91, and also pivotally secured to a shaft 202 (Fig. 4) which isadapted to support the two permanent cores |01, |08.

For this purpose the link 20| lhas a through bore 203 at .its lower end, and the lower end is rounded, as indicated at 208, to prevent interference with the mold parts.

consisting of two parts. Such a mold may be wood or of any suitable material, including metal.

The core may be made of a mixture of fuller's earth and kaolin in the proportions of 50 percent of fullers earth and 50 percent of kaolin, moistened by means of a suitable solvent, such as kerosene, to a moldable condition.

When a core has been molded out of this composition, as shown in Fig. 5, it is theny placed on a sheet of blotting paper, and the excess of kerosene is then taken up by the paper, while the molded core is permitted to dry at room temperature. The length of time in which drying is necessary depends upon the humidity and temperature of the room; but in ordinary summer weather the cores will dry in about an hour under these conditions.

After the cores have dried at room temperature, they are relatively rigid, and they are then dipped in a solution of water and silicate of soda.

This solution is suiiiciently thick to serve as a coating solution, and it may be of the consistency of paint. The strength of the resulting destructible core depends upon the consistency of the solution of sodium silicate and the period of time of immersion. The cores are preferably dipped in quickly, and then removed by means of pins or needles in order to make a thin shell of sodium silicate on the outside of the core.

The dipped cores are then baked at a maximum temperature of about 500 degrees F. The temperature is raised slowly to 500 degrees and haking carried on for a period of about two hours. During the baking and as the temperature is raised, the kerosene is volatilized, and driven out at a temperature of about 230 degrees F.

The water of combustion and of solution in the sodium silicate solution is driven out, and the sodium silicate is caused to harden, forming a destructible core, with a hard outer shell; and the interior of the core is soft and fluify. Such a sodium silicate shell is supported against the external pressures which are applied to it by the head of metal in the mold and in the ladle by means of the body of fullers earth and kaolin,

11 which also excludes most of the air from the destructible core.

However, the core is destructible; and when the metal goes into the mold, the air expands in the core and escapes through the conduits ISU- |62 and conduits |56, |51, |58, |59, through the permanent cores.

The castings may be quenched in water at about 1,000 degrees F., and the core may be removed at once by soaking the casting in the quenching water.

Cleaning out of the core may be eiected by means of the flow of water under pressure, leaving the through conduit 98 in the casting, with its outlet ports HS-I 48.

The mold is preferably provided with spring means for securing the two halves of the mold together and maintaining the removable mold half in the casting position. For example, each side of the xed half 8| of the mold may be provided with a pair of spring arms 2|0, 2| l, which may take the form of a strap of metal.

The'strap may have a' iiat attaching portion or yoke 2|2, which is welded, screwed, or otherwise secured to the rear side of the mold half 8|. At each side of the mold, such as, for example, the points 2|3, the strap is bent forwardly, and extends diagonally outward from the mold, forming the spring arms 2|0, 2| I. l

These spring arms are provided at their ends with partially cylindrical inwardly curved latching portions 2H, which are complementary in shape to the pipe handles 2|5 carried by the movable mold section 83. 'I'he curved portions 2H may extend over approximately one-fourth of a revolution, that is, they may extend far enough about the handles 2I5 to -have a portion of their curved surface in position to oppose directly any movement of the handles 2|5 and the movable mold half 83 away from the xed mold half 8|.

The handles 2|5 comprise short sections of tubular stock or pipe, which are xedly secured, as, for example, by welding, to the ends of the spring arms 2|6. For example, the pipe may be slotted, and the end of each spring arm inserted in the slot and welded in place.

The spring arms 2li also are provided With attaching anges 2H, which extend parallel to the sides of the movable mold half 83, and are secured to this mold half by welding, riveting, or screws, preferably the former.

The length of the spring arms 2 I6 and the direction in which they extend relative to the spring arms 2|0, 2|| is such that the latching shoulders 2H engage outside the tubular handles 2|5 and so that the arms 2|0, 2| 2|6 are in substantial alignment with each other when he mold halves are in closed position.

The arms 2|6 may be swung toward each other by means of lateral pressure applied to the handles 2|5, and thus the removable mold half may 'be removed. The arms 2|6, however, tend to swing out into the latching position and to hold the mold halves together in the closed position.

Referring to Figs. l, 2, and '1, the mold is preferably provided with means for ejecting the casting from the movable half of the mold, indicated in its entirety by the numeral 228 (Fig. 2). This may consist of a cross head 22| of' cruciformk shape, the four arms of which carry four pins or plungers 222-225.

Each of these plungers may consist of a cylindrical rod, having a portion ofreduced size, as indicated at'225 (Fig. 7), the reduced end portion cross head 22|. It may be secured by a -tight frlctional lit or by riveting over the end, or in any other suitable manner. The plungers 222- 225 are slidably mounted in the mold half 83, which is provided with through bores 228 for receiving these plungers, the bores being parallel and having a sliding fit with the plungers.

The plungers are provided on their inner ends with surfaces. complementary to that portion of the mold into which they may happenA toproject 'so that the ends of the plungers form a continuation of the mold surface in the cavity.

The plungers 222-225 and bores 228 are preferably symmetrically located with respect to the parts of the casting, and a lesser or a greater number of plungers may be used, as required, to assure the ejection of the casting from the movable half of the mold and its retention in the xed portion of the mold.

In other words, the plungers remove the movable mold half 83 from the casting and fixed mold half.

The plungers preferablyA engage the casting at some point Where the casting will not be marred by the engagement of the plungers. In the present case the plungers arev so arranged that they engage the casting at the attaching flanges |00- (03. The molds being cylindrical and the surfaces of these attaching flanges being plane or dat, the ends of the plungers may be at, and they form corresponding circular marks in the attaching anges I0-0-I03, which serve as marks for determining the location of the drill in drilling the apertures in these attaching flanges.

The cross head 22| is provided with a centrally located threadedV bore 229 for receiving the threaded shaft 230, which is provided with a cylindrical head 23|. The cylindrical head 23| is rotatably mounted in a socket 232 provided by a metal stirrup 233, which has attaching anges ggd welded to the outer surface of th'e mold half The stirrup 233 has a bore 235 for rotatably supporting the shank of the threaded shaft 230. The stirrup 233 serves as a thrust bearing for preventing the axial movement of the shaft 230 relative to the mold half 83. The shaft 230 is provided with a reduced noncircular portion 236 adapted to receive the complementary bore in the end of a crank 231, having a handle 238.

A nut or other suitable means is provided at 239 for securing the crank arm 231 on the reduced portion 236 of the shaft 230. When the crank is rotated by means of the handle 238, it rotates the shaft 230, and the threads on the shaft and in the bore 229 cause the cross head to progress along the shaft in one direction or another. When the cross head is driven inward, the plungers engage the attaching anges |00- I03 on the casting, and the shaft utilizes its head 23| to withdraw the mold half 83 from the casting and the fixed mold half 8|. The plungers react against the casting to remove the movable portion of the mold. The length of the shaft is preferably such that when the plungers are withdrawn to the iiush position inside the cavity, the cross head 'hits the lower side of the crank arm 231, thus assuring the continuity of the cavity at the point where the plungers are located.

The burner 59 may comprise an arrangement having a nozzle 53, which is directed into the opening 52 of the ladle, but which isv of such length that it may be rotated out of the aperim .lizA or it may be directed at diiierent angles.

In the present embodiment, nozzle 53 comprises a pipe secured in a bushing 240, which is in turn securedf'in a'n elbow 24|. The elbow 24| is carried by a horizontally extending pipe 242, and leads to a. second downwardly turned elbow 243, which is connected to a short section of pipe 244 leading to a flexible rubber hose 245.

The flexible rubber hose 245 is of suillcient length to form a substantially U-shaped curved portion -which is adapted to be bent when the ladle is tilted. The opposite` Yend of the hose is secured on another short pipe section 246 carried by the elbow 241.

The elbow 241 is connected by additional elbows 248 to a downwardly directed pipe 249, which' has two inlets 250, 25| to the air pipe 253 and the gas pipe 252. The two pipes 253, 252 are connected to appropriate supplies of air and illuminating gas, and are provided with valves so that the two gases may be mixed in proper proportion to be conducted to the nozzle 53, where they are burned upon issuing from the nozzle.

The assembly of pipes extending downward from the pipe 249 may be xed and secured to the framework or to the iloor while thus located, and connected to th'e opposite end of the hose 245.

Another modified form of destructible core for casting may be constructed and handled as follows: Asbestos fibers and kaolin may be mixed together in the proportions of equal parts by volume of asbestos and kaolin. The asbestos bers may be of the chrysotile type or the Amosite type.

The mixture of kaolin and asbestos may be moistened with kerosene, which has the advantage that it does not cause the core to adhere to the mold; but, on th'e contrary, makes it easily separable from the mold.

This plastic mixture may then be molded into the proper shape for the destructible core, and pressure is applied to squeeze out the excess of kerosene, after which the cores are laid out upon a blotting paper, or similar material, to dry, the cores being handled by means of pins or needles, which may project intoportions of the core and provide handles. The blotting paper takes up such' of the kerosene as will separate by gravity from the relatively dry and hard cores; and in the proper use of such cores they may be produced in a continuous series, if possible, so that they may be used from one end of the stream and built at the other end.

It is also possible, however, to let the cores stand for a considerable length of time after they have been molded, as the presence of kerosene in the core at this stage prevents it from absorbing moisture from the air.

After the cores have dried on the blotting paper, they may then be dipped in a solution of sodium silicate of such a consistency that it provides a coating composition. The sodium silicate coats the exterior of the cores. Instead of baking the cores, as previously described, the operator may then ignite the cores a little while before it is necessary to use them, by applying a match. The kerosene will cause the cores to be burned so that the kerosene will be burned out of the core, even though the core is covered by the sodium silicate. The water will then be evaporated out of the sodium silicate, leaving only the salts, and the core will be free of all liquid when it has finished burning, and will be provided with a relatively hard exterior surface.

Such cores after being burned, remain hot for 14 a considerable length of time so that they can be used as desired, if the casting is proceeding uniformly and the hot cores are used in the casting in the usual Way.

There are a number of different waysof removing the cores after the casting has solidiiled and cooled:

1. The cores may bed picked out by means of a picking tool, which effectively tears them to pieces and withdraws them from the ycavity which the core has formed.

2. They may be drilled out or removed by any other mechanical tool.

3. The castings may be placed in water, whereupon the cores will absorb the water and disintegrate so that their removal can be expedited by picking at them mechanically.

4. The cores may be dissolved by immersion of the casting in water, and forced out by water under the pressure.

The advantages of these cores are as follows:

1. They form relatively perfect cavities in the castings, and they may be made of any desired shape.

2. There is no tendency to absorb moisture in the air if the cores are used quite promptly after having been burned out.

3. They do not tend to stick to the walls of the cavity.

4. They form a relatively smooth cavity, due to the outer crust of the salts from the sodium silicate solution.

5. The destructible cores are easily removed from the casting. v

6. They have the advantage over permanent cores that they do not have to be preheated like permanent cores, and they do not have to be tapered or otherwise shaped so that they can be retracted from the cavity which they are to'form.

Referring to Figs. 'l to 10, these are views which show the mold and a part of the ladle in the different positions which they assume during the making of the casting.

In Fig. 7 the -mold is shown on top of the ladle, with the mold halves closed, and the cores in proper position. The mold is empty, but has been preheated by the application of the ame from the burner 53, which projects a flame into the ladle, the flame being reflected from the free surface of the metal into the mold. After the rst casting hasbeen made, the mold is maintained in heated condition by the heat which it takes from the molten metal as the metal congeals.

Assuming, the metal and the mold to be at the proper temperatures, the ladle may be tilted from the full line position of Fig. 6 to a position where the major axis of the mold extends substantially horizontally, that is, until the mold is lled and the head of metal in the ladle is 1ocated above the mold cavity.

vThis tilting motion may be suitably timed, and should be carried 'out steadily and gradually, depending on the size of the casting.

As the ladle and mold tilt toward the left from the position of Fig. 7 to that of Fig. 8, the molten metal will Well up into the mold cavity about the ends of the permanent cores |01, |08, gradually filling the cavity as shown in Fig. 8.

The free surface of the metal in the mold cavity is, of course, always at the same level as that in the ladle. The metal wells up without any separation, splashing, or spurting until the mold is filled and the tilting may be continued to raise the free surface of the metal in the ladle sub- 15 stantially above the mold cavity to the position shown in Fig. 9.

This places a predetermined head of metal on the molten metal in the cavity of the mold, and the pressure assures the lling of the mold at all points.

As the lling of the mold cavity progresses, the air passes out of the grooves |23 and H9 at the edges of the mold cavity, and any gases that are generated by the heating of air or volatilization of any of the constituents of the destructibie core |09 may pass out through the apertures |60 and apertures 456, |58 or apertures |62, |51, |59 in the permanent cores |08, |01. The tilting may be continued, if desired, until the mold is substantially inverted, as the invertion of the mold may be desirable by reason of the fact that the position of the casting corresponds to the natural heat gradient of heated bodies. Under these conditions the castings will be cooler at the bottom.

The casting congeals from the outside surfaces of the casting inward and from the surfaces of the permanent cores outward, forming an inner and outer shell first, after which further congelation progresses from that part of the casting that is most remote from the ladle, down toward the lling opening. y

As this congelation takes place, there is a shrinkage of the casting, which, however, is taken up by the supply of additional metal to the space between these two initial shells. The point to which congelation takes place may be indicated by any of the dotted lines seen at the bottom of the casting in Fig. 10, depending upon the time when the mold and ladle are tilted back to the initial position.

Fig. 10 shows the casting after the casting has congealed and the mold is ready to be opened. Thus the sprue may be made long or short, but as long as the perfect part of the casting extends to the point where the sprue is to be cut oi, no harm is done.

The molten portion of metal in the fllling conduit which is not congealed ows back into the ladle. The portions of sprue which are cut off may also be thrown back into the furnace to be remelted and used over. The amount of sprue is so small that the characteristics of the molten metal are not materially changed by remelting and using these small sprues.

The casting having congealed, the permanent cores may be removed by pulling upward on the lever |89. This lever is adapted to apply a substantial lifting force to the permanent cores |01, |08 by reason of its length; and it may be necessary to jar the lever upward initially by means of va blow with the heel of the hand, after which the lever may be moved up steadily until the cores are removed.

During this motion of the permanent cores the ends of the destructible core |49, which are in the sockets |53, |54, |55, will be sheared off.

The mold halves may then be separated by turning the crank arm 231 in a clockwise direction, which will cause the cross head 22| to approach the mold half 83, and the plungers 222- 225 will bear against the casting, while the threaded member 230 withdraws the mold half 83. The springs 2 I0 are forced apart by the threaded member 230, portions 2H acting as cams.

The ends of the plungers 222-225 make marks on the attaching iianges H10-|03 which serve to indicate where holes should be drilled, and after +1.., ne n1 mi threaded member 230 have been used to initiate the removal of the mold haii' 83 from the casting and the mold half 8|, the handles 2I5 may be sprung together, and the entire mold half 83 removed by hand.

The filling opening 1E in the plate 15 preferably tapers downward, and the lling conduit 51 in the refractory member 11 also tapers downward so that any sprue which is located either in the openings 51 or 16 can be removed in an upward direction without difficulty. Where these conduits are not tapered downward, arrangements may be made for separating the refractory member 11 into two halves also.

The casting and sprue are then pried out of the fixed mold half BI, and the casting may be quenched at once by being placed in water, which will initiate the dissolution of the destructible core. Then the removal of the destructible member may be completed according to any of the.

If this is not done, the permanent cores will be in such position that there is no room to get the ends of the destructible core in the sockets. Therefore, the destructible core and the permanent cores must first be assembled, and then the assembly of cores moved down into the mold.

The method of making destructible cores has already been described herein in several different ways. The method of casting may be brief-ly summarized as follows:

The ladle is preferably supplied with metal from a plurality of furnaces which hold the metal in batches, and batches are successively supplied to the ladle from the furnaces in rotation. The temperature of the furnace is maintained at a higher degree than the ladle in order that the heat which is supplied to the metal in the furnace may be used to elevate and maintain the temperature of the ladle and mold.

The temperatures which are given herein are exemplary and vary with the different alloys or metals to be cast. For example, the alloy No. 356 of the Aluminum Company of America having a composition of 7% silicon, 0.03% magnesium and the rest aluminum may be used for casting; and in this case I prefer to keep the temperature of the furnace within a range of not less than 1250 degrees F. and not more than 1300 degrees F. The temperature of the metal in the ladle will depend upon the type of casting being produced; and when the present castings are produced I prefer to maintain the metal in the ladle between 1175 degrees F. and 1200 degrees F.

For casting thin plates of this alloy the temperature in the ladle might be maintained between 1225 degrees F. and 1250 degrees F,

The characteristics of this alloy are given in certain standard tables as having a solidifying temperature ranging from 1075 degrees F, to 1130 degrees F. Thus the temperature of the metal in the ladle is preferably maintained as close as possible to the melting temperature of the metal used in casting, that is, slightly above the solidifying temperature, so that when cast the metal solidies quickly in the mold.

Less time is required for casting, and any tendency toward segregation is minimized by quicker congelation.

Segregation ordinarily takes place during congelation. Quicker congelatlon reduces or substantially prevents the segregation of impurities or of the ingredients of an alloy.

This close to congelation temperature is maintained by frequent measurement, and constant observation of indicated temperature of the molten metal in the ladle and of that in the furnace; by adjustment of the furnace and ladle temperature, by regulating the heating arrangements of the furnace, or of the ladle: and by replenishing the ladle supply at proper time and temperature.

The ladle gas burner can be adjusted to higher or lower heat, or if the metal or ladle or furnace is too hot, a small solid piece of clean metal can be thrown in to absorb heat by reason of the fact that it will be heated and melted.

With the metal in the ladle and the mold at the proper temperature, and the flame blowing on the filling opening of the mold, by reiiection from the free surface of the metal, and all of the parts in proper position for casting, the casting operation may then be started.

The ladle should be provided with a clean supply oi' molten metal, and any dross or scum should be skimmed H by using a skimming member through the opening 52, and the oxygen should be excluded from the space above the molten metal by means of the flame and gases from the burner 53.

The operator may use the pipe 242 as a handle, and the ladle and mold are tilted forward, that is, toward the left in Fig. 6, causing the free surface of the metal to approach the filling opening. Since the metal is clean and has been skimmed, nothing but clean metal wells up into the conduit 68, leading to the mold; and as the ladle and mold are tilted, the metal gradually wells up into the mold cavity, as shown in Fig. 8.

While this is going on, the air is being discharged through the grooves around the top of the mold and through the air bleeders in the permanent cores, and the tilting is continued until the mold is completely filled.

The arrangement of the mold with respect to the incoming stream of metal is preferably such that at no time does the metal, which is filling the mold, separate from the main body of the metal, but in some cases it may be necessary, with complicated castings, to diverge slightly from this preferred procedure. In any event, the complete mold is filled with molten metal when the mold reaches the position of Fig. 9, and the ladle has a head of molten metal above that in the mold.

The casting is then caused to congeal from the point most remote from the ladle, inward toward the ladle; and it also congeals inward from the sides of the mold cavity and outward from the permanent cores.

This results in this particular casting in the formation of a double shell, the walls of the shell being separated by molten metal, which continues to congeal backward, toward the ladle. As the casting congeals, there may be shrinkage, which is taken up by the supply of additional molten metal from the ladle under pressure, due t0 gravity. When the metal has congealed to the desired point to form a complete casting, with a minimum amount of sprue, the mold and ladle are tilted back to the position of Fig l0, and the 18 dotted lines of lower pipe formations in the sprue indicate possible lengths of the sprue.

The sprue is preferably kept as short as possible, and the timing may be gauged in a few minutes by making a few castings. The rest ot the molten metal flows back into the ladle, and the mold is now preferably promptly removed from the casting, as follows:

The permanent cores are withdrawn by means of the handle |15. The mold half 83 is withdrawn from the casting and mold hall 8l by means of the threaded member 230. The casting is then pried out of the mold half 8|, taking with it such sprue as may remain on the casting; and due to the downward taper of the opening, ex-

tending downward from the mold cavity to the' ladle, the sprue can be removed with the casting.

The casting is then preferably quenched in water, or some other suitable liquid which will dissolve the destructible core. The destructible core may be removed by picking with a mechanical tool or by flushing it out with water under pressure.

The sprue is then cut off at an appropriate' point, and holes may be drilled in the attaching flanges of the casting.

It will be observed that I have invented an improved casting machine and a casting method by means of which castings of better characteristics and finish may be made than in any of the prior art devices.

be formed in the casting during the casting operation, thereby saving a great deal of machining;l and due to the finished surface of the castings,l

there is no machining necessary on the outside.'

In the present casting itis, of course, necessary The present castings are adapted to withstand' a higher pressure per square inch than any 'of the castings made according to prior art methods. They are nonporous and absolutely sound. They are free from fiaws, fissures, segregations, surface defects and other defects.

While I have illustrated a preferred embodiment of my invention, many modifications may be made without departing from the spirit of the invention, and I do not wish to be limited to the precise details of construction set forth, but desire to avail myself of all changes within the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States, is:

l. A permanent mold comprising a member of steel which is formed of a plurality of steel plates having upper and lower plane surfaces, the said steel plates being secured together in alignment by means of a plurality of dowel members, said mold comprising two halves, each of which is formed with a mold cavity, the said cavities, when the molds are assembled, having a recess for a pair of substantially cylindrical barrels arranged substantially parallel to each other and provided with a joining body between said barrels, the said cylindrical barrels being of larger cross section at each end and provided with an intermediate portion of smaller cross section, and the said plates including a central plate of substantially By means of my destructlble cores, various types of apertures or conduits may portion of reduced size, the said mold being formed at its upper end with a pair of cylindrical apertures for receiving a pair of substantially cylindrical plugs, and each of said plugs having centrally located therein a core member for forming a through bore in each of the 'barrels of said casting.

2. A permanent mold comprising a member of steel which is formed of a plurality of steel plates having upper and lower plane surfaces, the said steel plates being secured together in alignment Iby means of a plurality of dowel members, said mold comprising two halves, each of which is formed with a mold cavity, the said cavities, when the molds are assembled, having a recess for a pair of substantially cylindrical barrels arranged substantially parallel to each other and provided with a joining body between said barrels, the said cylindrical barrels being of larger cross section at each end and provided with an intermediate portion of smaller cross section, and the said plates including a central plate of substantially the same thickness as the length of said central portion of reduced size, the said mold being formed at its upper end with a pair of cylindrical apertures for receiving a pair of substantially cylindrical plugs, and each of said plugs having centrally located therein a core member for forming a through bore in each of the barrels of said casting, the said cores being formed with sockets for receiving the ends of a substantially Y shaped destructible core member adapted to form a conduit leading from the bore of one barrel to the bore of the other barrel.

3. A permanent mold comprising a member of steel which is formed of a plurality of steel plates having upper and lower plane surfaces, the said steel plates being secured together in alignment by means of a plurality of dowel members, said mold comprising two halves, each of which is formed with a mold cavity, the said cavities, when the molds are assembled, having a recess for a pair of substantially cylindrical barrels arranged substantially parallel to each other and provided with a joining body between said barrels, the said cylindrical barrels being of larger cross section at each end and provided with an intermediate portion of smaller cross section,` and the said plates including a central plate of substantially the same thickness as the length of said central portion of reduced size, the said mold being formed at its upper end with a pair of cylindrical apertures for receiving a pair of substantially cylindrical plugs, and `each of said plugs having centrally located therein a core member for forming a through bore in each of the barrels of said casting, the said cores being formed with sockets for receiving the ends of a substantially Y shaped destructible core member adapted to form a conduit leading from the bore of one barrel to the bore of the other barrel, the said cores being provided with vents leading from said sockets to the external atmosphere for venting any gas resulting from the heating of the said destructible core.

4. A permanent mold comprising a member of steel which is formed of a plurality of steel plates having upper and lower plane surfaces, the said steel plates being secured together in alignment by means of a plurality of dowel members, said mold comprising two halves, each of which is formed with a mold cavity, the said cavities, when the molds are assembled, having a recess for a pair or substantially cylindrical barrels arranged substantially parallel to each other and provided with a joining body between said barrels, the said cylindrical barrels being of larger cross section at each end and provided with an intermediate portion of smaller cross section, and the said plates including a central plateloi substantially the same thickness as the length of said central portion of reduced size, the said mold being formed at its upper end with a pair of cylindrical apertures for receiving a pair of substantially cylindrical plugs, and each of said plugs having centrally located therein a core member for forming a through bore in each of the barrels of said casting, the said plugs being formed with` annular limiting flanges for engaging the outside of the mold assembly and determining their nal position.

5. A permanent mold comprising a member of steel which is formed of a plurality of steel plates having upper and lower plane surfaces, the said steel plates being secured together in alignment by means of a plurality of dowel members, said mold comprising two halves, each of which is formed with a mold cavity, the said cavities, when the molds are assembled, having a recess for a pair of substantially cylindrical barrels arranged substantially parallel to each other and provided with a joining body between said barrels, the said cylindrical barrels being of larger cross section at each end and provided with an intermediate portion of smaller cross section, and thesaid plates including a central plate of substantially the same thickness as the length of said central portion of reduced size, the said mold t being formed at its upper end with a pair of cylindrical apertures for receiving a pair of substantially cylindrical plugs, and each of said plugs having centrally located therein a core member for forming a through bore in each of the barrels of said casting, the said plugs being formed with annular limiting flanges for engaging the outside of the mold assembly and determining their ilnal position, and the said plugs being formed in .their external cylindrical surface with a plurality of longitudinally extending grooves also located in the under-side of said annular flange for venting air from the upper part of said mold at the outside corners of the cavity,

6. A permanent mold comprising a member of steel which is formed of a plurality of steel plates having upper and lower plane surfaces, the said steel plates being secured together in alignment by means of a plurality of dowel members, said mold comprising two halves, each of which is formed with a mold cavity, the said cavities, when the molds are assembled, having a recess for a pair of substantially cylindrical barrels arranged substantially parallel to each other and provided with a joining body between said barrels, the said cylindrical barrels being of larger cross section at each end and provided with an intermediate portion of smaller cross section, andthe said plates including a central plate of substantially the same thickness as the length of said their final position, and the said plugs being formed in their external cylindrical surface with a plurality of longitudinally extending grooves also located in the under-side of said annular flange for venting air from the upper part of said mold at the outside corners of the cavity, and the said plugs also having internalgrooves 4forming vents in connection with their cores at the inner upper corner of the mold adjacent the cores.

7. A permanent mold comprising a, member of steel which is formed of a plurality of steel plates having upper and lower plane surfaces. the said steel plates being secured together in alignment by means of a plurality of dowel members, said mold comprising two halves, each of which is formed with a mold cavity, the said cavities, when the molds are assembled, having a recess for a pair of substantially cylindrical barrels arranged substantially parallel to each other and provided with a joining body between said barrels, the said cylindrical barrels being of larger cross section at each end and provided with an intermediate portion of smaller cross section. and the -said plates including a central plate oi substantially the same thickness as the length of said central portion of reduced size, the said mold having its lower end open and being securedto a substantially wedge shaped insulating body which is carried by a metal plate, and means for insulating said metal plate for a ladle.

8. A permanent mold comprising a member of steel which is formed of a plurality of steel plates having upper and lower plane surfaces, the said steel plates being secured together in alignment by means of a plurality of dowel members, said mold comprising two halves, each ofl which is formed with a mold cavity, the said cavities, when the molds are assembled, having a recess for a pair of substantially cylindrical barrels arranged substantially parallel to each other and provided with a joining body between said barrels, the said cylindrical barrels being of larger cross section at each end and provided with an intermediate portion of smaller cross section, and the said plates including a central plate of substantially the same thickness as the length of said central portion of reduced size, one of the halves of said mold having a plurality of plungers extending through it into engagement with a casting formed in the cavity. and force multiplying means for withdrawing said latter half of the mold while causing said plungers to react against a casting in the cavity.

9. In a mold of the permanent type, the combination of a pair of mold members. each of said mold members being formed with a portion of a cavity, means for maintaining the proper alignment of said mold members and for securing the said mold members together, the said mold members being provided with substantially plane engaging surfaces bordering the cavity portions formed in them and the said mold being closed at its outer end and provided at its inner end with a filling opening for direct communication with a member containing a supply of molten metal, the cracks between the mold members being of such size as to permit air to escape between them, one of said mold members being fixed. and the other one being movable, and force multiplying means for actuating a plurality of plungers, the said piungers passing through one of said mold members and engaging the casting to separate the mold members and cause the casting to be retained by the other mold member, said force multiplying means including a screw acting on a, cross head supporting said plungers.

10. In a mold of the permanent type. the com 4bination of a pair of mold members, each of said mold members being formed with a portion of a cavity, means for maintaining the proper alignment of said mold members and for securing the said mold members together, the said mold members being provided with substantially plane engaging surfaces bordering the cavity portions formed in them and the said mold being closed at its outer end and provided at its inner end with a filling opening for direct communication with a. member containing a supply of molten metal. the cracks between the mold members being of such size as to permit air to escape between them,l the closure of the outer end of said mold being accomplished by means of a removable slidable closure, and force multiplying means for removing said outer end closure, the said closure supporting a longitudinally extending core located in said cavity, and said core being removable with said closure, said core having a laterally extending recess, and a second core extending laterally from the first-mentioned core and located in said recess to form a laterally extending passage inside a portion of said casting, one of said cores being destructible to facilitate the withdrawal of the first-mentioned core by shearing action.

11. In a mold for casting, the combination of a pair of mold members, each of which is formed with a portion of the cavity. the said mold members having opposed engaging plane faces, said mold having a pair of openings at the outer end of its cavity for receiving a pair of cores, whereby the casting is formed with a pair of bores, a core in each opening and said cores being with opposed recesses for receiving the ends of a destructible core forming a, transverse conduit between said bores, a destructible core carried in said recesses, whereby the said destructible core is sheared off at said recesses by the withdrawal of either of the first-mentioned cores when the casting is completed. l

12. In a mold for casting, the combination of a pair of mold members, each of which is formed with a portion of the cavity, the said mold members having opposed engaging plane surfaces, said mold. having a pair of openings at the outer end of its cavity for receiving a pair of cores, whereby the casting is formed with a pair of bores, a core in each opening and said cores being provided with opposed recesses for receiving the ends of a destructible core forming a transverse conduit between said bores, a destructible core car ried in said recesses, whereby the said destructible core is sheared oi at said recesses by the withdrawal of either of the first-mentioned cores when the casting is completed, the said recesses com'- municating through air apertures in said cores with the external atmosphere to discharge any gases formed in the vicinity of said destructible core.

CARL vi/Essai...v REFERENCES erre The following references are of record in the file of this patent:

UNITED STATES PATENTS (Other references on following page) provided Number Number 24 Name v Date Morris Apr. 2, 1940 Bierbaum May 4, 1915 Kuhler Oct. 11, 1938 Wessel Jan. 28, 1943 Hagemeyer Oct. 13, 1942 Almen June 23, 1936 Hannan Sept. 8, 1931 Wessel June 30, 1942 

